Electron gun,cathode-ray tube and projector

Abstract

In a cathode ray tube equipped with an electron gun for radiating multiple electron beams each scanning different positions, it is made possible to modulate velocities of the electron beams individually. There are provided a first velocity modulation coil ( 9 ) for generating a magnetic field H 1 that exerts force F 1 on the first electron beam I 1 and a second velocity modulation coil ( 10 ) for generating a magnetic field H 2 that exerts force F 2 different from the force F 1 on the second electron beam I 2 . In the cathode ray tube, by modulating the velocities of the electron beams I 1 and I 2 independently of each other, it is possible to improve sharpness without deteriorating a grade of an image. Further, in a projector equipped with the cathode ray tube, it is possible to improve luminance and also improve sharpness without deteriorating the image grade.

1 . An electron gun for radiating multiple electron beams, said electron gun comprising a velocity modulation electrode for generating an electric field that exerts force individually on each of said electron beams.  
     
     
         2 . The electron gun according to  claim 1 , wherein a grid electrode is used as said velocity modulation electrode.  
     
     
         3 . A cathode ray tube equipped with an electron gun for radiating multiple electron beams, wherein said electron gun comprises a velocity modulation electrode for generating an electric field that exerts force individually on each of said electron beams to thus modulate a scanning velocity thereof.  
     
     
         4 . The cathode ray tube according to  claim 3 , wherein a grid electrode is used as said velocity modulation electrode.  
     
     
         5 . The cathode ray tube according to  claim 3 , wherein the number of said electron beams radiated from said electron gun is two for each color.  
     
     
         6 . A cathode ray tube equipped with an electron gun for radiating multiple electron beams, comprising a velocity modulation coil for generating a magnetic field that exerts force individually on each of said electron beams radiated from said electron gun.  
     
     
         7 . The cathode ray tube according to  claim 6 , wherein said velocity modulation coil is incorporated into a deflection yoke for deflecting said electron beams.  
     
     
         8 . The cathode ray tube according to  claim 6 , wherein the number of said electron beams radiated from said electron gun is two for each color.  
     
     
         9 . A projector equipped with three monochromatic cathode ray tubes for red, green, and blue, each of said cathode ray tubes being provided with an electron gun for radiating multiple electron beams, wherein each of said electron guns comprises a velocity modulation electrode for generating a electric field that exerts force individually on each of said electron beams to thus modulate a scanning velocity thereof.  
     
     
         10 . The projector according to  claim 9 , wherein a grid electrode is used as said velocity modulation electrode.  
     
     
         11 . The projector according to  claim 9 , wherein the number of said electron beams radiated from said electron gun is two for each color.  
     
     
         12 . A projector equipped with three monochromatic cathode ray tubes for red, green, and blue, each of said cathode ray tubes being provided with an electron gun for radiating multiple electron beams, comprising a velocity modulation coil for generating a magnetic field that exerts force individually on each of said electron beams radiated from said electron gun to thus modulate a scanning velocity thereof.  
     
     
         13 . The projector according to  claim 12 , wherein said velocity modulation coil is incorporated into a deflection yoke for deflecting said electron beams.  
     
     
         14 . The projector according to  claim 12 , wherein the number of said electron beams radiated from said electron gun is two for each color.